1 /* * Copyright (c) 2021 Apple Inc. All rights reserved.
2 *
3 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
4 *
5 * This file contains Original Code and/or Modifications of Original Code
6 * as defined in and that are subject to the Apple Public Source License
7 * Version 2.0 (the 'License'). You may not use this file except in
8 * compliance with the License. The rights granted to you under the License
9 * may not be used to create, or enable the creation or redistribution of,
10 * unlawful or unlicensed copies of an Apple operating system, or to
11 * circumvent, violate, or enable the circumvention or violation of, any
12 * terms of an Apple operating system software license agreement.
13 *
14 * Please obtain a copy of the License at
15 * http://www.opensource.apple.com/apsl/ and read it before using this file.
16 *
17 * The Original Code and all software distributed under the License are
18 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
19 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
20 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
21 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
22 * Please see the License for the specific language governing rights and
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24 *
25 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
26 */
27
28 #include <libsa/string.h>
29 #include <mach/vm_types.h>
30 #include <machine/static_if.h>
31
32 void
ml_static_if_entry_patch(static_if_entry_t sie,int branch)33 ml_static_if_entry_patch(static_if_entry_t sie, int branch)
34 {
35 uint8_t insn[STATIC_IF_INSN_SIZE] = { 0x0F, 0x1F, 0x44, 0x00 };
36 vm_offset_t patch_point = __static_if_entry_patch_point(sie);
37
38 if (branch) {
39 int32_t delta = (int32_t)(sie->sie_target -
40 (sie->sie_base + STATIC_IF_INSN_SIZE));
41 insn[0] = 0xE9; /* jmp 32 */
42 memcpy(insn + 1, &delta, sizeof(delta));
43 }
44
45 bcopy(insn, (void *)patch_point, STATIC_IF_INSN_SIZE);
46 }
47
48 void
ml_static_if_flush_icache(void)49 ml_static_if_flush_icache(void)
50 {
51 }
52